It's a single elimination BO3 with 16 players, me and someone else have been promoted to Platinum since the start and everyone else is in Gold. So it's a medium level small tournament.
Still this is my first experience of such a thing and I'm enjoying it! I've won the first 2 games 2:1 with every game being more nervewracking than playing on the ladder!
Tournament bracket image (I'm x78): http://i.imgur.com/Ow14G.jpg
Maybe one day I'll be in the GSL.. you never know!
Zerg fighting and all that!
Wish me luck!